With the Maple Leafs boasting a deep group of defensemen, there will naturally be competition for ice-time. Beyond Dion Phaneuf, Luke Schenn and John-Michael Liles – the sure things – the Leafs still possess one-time marquee free agent Mike Komisarek, summer addition Cody Franson, and Carl Gunnarsson, whose poise earned him increased ice-time as the season went on.

None of those latter three are currently being slated for a top-four role, however. Instead, it seems highly likely that Keith Aulie, the 22-year old who came over from Calgary with Dion Phaneuf, will start the season as Phaneuf’s partner in the top-four. Is he ready for that role?

Last season, Aulie played his first game with the Maple Leafs in November, playing 14:00 and going minus-1 in a loss to Vancouver. In a dozen games over that stint with the blue and white, his ice-time was carefully limited – he played less than 10:00 on two occasions and played more than 20:00 just once. He was re-assigned to the minors midway through December and kept there until mid-February.

Aulie’s second call-up was handled very differently, though. With Komisarek and the much-maligned Brett Lebda in free-fall, Aulie immediately stepped on to the second pairing, playing 21:56 in his first game back in the NHL on February 10. He’d be a fixture in a top-four role for the remainder of the season, routinely logging over 20:00 per night and never playing less than 16:27.

Aulie wasn’t given gentle minutes, either. He started in his own end of the rink more than 55% of the time – among regulars on the Leafs’ blue-line, only Mike Komisarek had a nastier zone start than that. Behind the Net, the advanced statistics website, lists three different ways of evaluating quality of competition – Aulie led the Leafs’ blue-line in all three. There is arguably no more difficult job for a rookie defenseman than being asked to start night after night in his own end against the best players the other team can send out.

Baseball these days, relies heavily on statistical analysis to mine previously unrecognized talent. The philosophy was made famous last year by the Michael Lewis bestseller "Moneyball." Wilson said he found Lewis's book "interesting, because I've been doing something similar for 10 years in hockey."

Aulie’s numbers are really, really good. Looking at just those numbers, we might come to the conclusion that he is the best shutdown defenseman on the team – particularly given the role he was playing

There is another set of numbers we could connect to shutdown ability, however – instead of looking at a players goals against average, we could look at their shots against average; in other words, the number of shots against in 5-on-5 situations that occurred with those players on the ice. What would that chart look like?

Player

GAON/60

SAON/60

Carl Gunnarsson

2.55

28.1

Luke Schenn

2.64

28.5

Brett Lebda

3.65

28.7

Dion Phaneuf

2.49

29.2

Michael Komisarek

2.89

29.9

Keith Aulie

2.22

33.6

So, Aulie has both the best goals-against average and the worst shots-against average. How is that possible?

Many would argue that shots are different than scoring chances, and that Aulie was probably doing a good job of blocking key parts of the ice, forcing his opponents to take low-quality shots. While that’s possible, a comprehensive study of NHL defensemen shows the following:

The ability of defensemen to affect shot quality against does exist in the population, but it is so small that we will never be able to sensibly apply it to any player in particular. And a paradox is created, the type of defensemen who are helping the goalie save percentage a bit (presumably because they make fewer mistakes of the spectacularly bad variety) are, as a group, seeing slightly worse save percentages behind them, because they are the guys the coaches are leaning on to play tougher opposition.

In other words, there isn’t a big gap between various defensemen in their ability to limit shot quality – and the guys who are good at limiting shot quality generally play against players that take high-end shots. We know that Aulie was playing against the best possible opponents, so his job would have been tougher still. In short, it seems unlikely that the reason for the difference between Aulie’s shots/goals-against totals can be attributed to his defensive efforts alone. Is there another explanation?

There is another possible explanation, one that I would argue is more likely, though naturally it will be up to individual readers to determine what they believe. What is it?

Earlier, I went into some detail on Aulie’s season – how he played limited minutes during his first call-up, and then played heavily from early February on. That wasn’t the only change in Toronto at around that time period.

From February 10 on, James Reimer played between the pipes for 26 of 28 games (92.9%). He had played in just 11 of the preceding 54 games (20.4%). With Reimer tending the nets, the Leafs went on a late season run – not enough to get them into the playoffs, but enough for Reimer to post a 20-10-5 record. Naturally, Reimer was responsible for much of the improvement – his 0.921 SV% far outshines those of teammates Jean-Sebastien Giguere (0.900) and Jonas Gustavsson (0.890). Was Reimer’s strong save percentage reflected in Aulie’s numbers?

Let’s look at that list of defensemen again, this time sorted by on-ice save percentage in 5-on-5 situations:

Player

GAON/60

SAON/60

On-Ice SV%

Keith Aulie

2.22

33.6

0.938

Dion Phaneuf

2.49

29.2

0.921

Carl Gunnarsson

2.55

28.1

0.917

Luke Schenn

2.64

28.5

0.915

Michael Komisarek

2.89

29.9

0.912

Brett Lebda

3.65

28.7

0.887

Aulie’s on-ice save percentage is far-and-away the best of the group, and that’s probably attributable in large part to playing the vast majority of his minutes in front of James Reimer.

Revisiting the question posed above, is Aulie ready for a top-four role? He is both young and capable of continued growth, but his numbers from last season cast some doubt. At the very least, it shouldn’t surprise anyone if he ends up on the ice for more goals against this season - particularly if he once again ends up on the ice for more shots against than any other defenseman.

Jonathan Willis is a freelance writer.
He currently works for Oilers Nation, Sportsnet and Bleacher Report.
He's co-written three books and worked for myriad websites, including the Edmonton Journal, Grantland, ESPN, The Score, and Hockey Prospectus. He was previously the founder and managing editor of Copper & Blue.

Interesting stuff. Even more so because I am just finishing up Moneyball. It has always seemed like its so hard to assess defensive defensemen because it's impossible to separate them from the goalie that plays behind them. It also seems as though Wilson will assign ice-time based on GAON/60, I wonder if that will dictate Franson and Liles roles.

Possibly. But every defenseman on the team is going to have the benefit of playing with Reimer, so if Aulie's on the ice for a ton of shots against again this year, it's hard not to imagine his plus/minus trailing the group.